Akin, a Republican who is challenging Democratic Senator Claire McCaskill for her seat, said in a local television interview that he “understand[s] from doctors” that rape-induced pregnancies are “really rare.”

“If it’s a legitimate rape, the female body has ways to try to shut that whole thing down,” added Akin, a member of the House Committee on Science, Space and Technology.

“Governor Romney and Congressman Ryan disagree with Mr. Akin’s statement, and a Romney-Ryan administration would not oppose abortion in instances of rape,” Romney campaign spokeswoman Amanda Henneberg said in a statement Sunday.

Romney offered a stronger condemnation Monday morning in an interview with the National Review.

“Congressman’s Akin comments on rape are insulting, inexcusable, and, frankly, wrong,” Romney said. “Like millions of other Americans, we found them to be offensive.”

Last year, Ryan joined Akin as one of 227 co-sponsors of a bill that narrowed an exemption to the Hyde Amendment, which prohibits federal funding for abortions. The Hyde Amendment allows federal dollars to be used for abortions in cases of rape and incest, but the proposed bill—authored by New Jersey Representative Christopher H. Smith—would have limited the incest exemption to minors and covered only victims of “forcible rape.”

House Republicans never defined what constituted “forcible rape” and what did not, but critics of the bill suggested the term could exclude women who are drugged and raped, mentally handicapped women who are coerced, and victims of statutory rape.

The “forcible” qualifier was eventually removed before the bill passed in the House last May. The Democrat-controlled Senate did not vote on the measure.

On Friday, before the Akin remarks, President Obama’s reelection campaign launched a television ad in six swing states accusing Romney and Ryan of opposing abortion “even in cases of rape and incest.”

On Monday, the Obama camp charged Romney and Ryan with “contradicting their own records” as they rejected Akin’s comments. In a statement, Obama spokeswoman Lis Smith referenced Ryan’s co-sponsorship of the “forcible rape” bill and Romney’s stated support of a Human Life Amendment, which she said “would ban abortion in all instances, even in the case of rape and incest.”

The Romney campaign dismissed the criticism as “another in a string of false attacks by the Obama campaign.”

“Mitt Romney’s position is clear: He is pro-life,” Henneberg said. “He opposes abortion with exceptions for rape, incest, or to save the life of the mother. The Obama campaign is attempting to scare voters with false charges in an effort to distract from President Obama’s litany of failures in office.”

The term “Human Life Amendment” covers a series of legislative efforts to grant full human rights to fertilized eggs. Some versions have included rape and incest exceptions to a constitutional ban on abortion; others have not.

Romney has said he supports an amendment that would mark conception as the beginning of life and that he would have signed such a bill at the state level, if one had crossed his desk as Massachusetts governor. He also has said a federal Human Life Amendment—which would require passage in both houses of Congress and approval by 38 of 50 states—is unrealistic and that the Supreme Court should overturn Roe v. Wade and allow states to write their own abortion laws.

“We have to decide what politically has the greatest potential of being successful,” Romney said in an interview with Mike Huckabee on Fox News last October.

“Would it be wonderful if everyone in the country agreed with you and me that life begins at conception, that there’s a sanctity of life that’s part of a civilized society, and that we’re all going to agree we’re not going to have legal abortion in the nation?” Romney asked Huckabee. “That’d be great, but I don’t think that’s where we are right now.”

Romney—a devout Mormon who has maintained a consistent, personal opposition to abortion—has altered his political position on abortion over the years. As a Senate candidate in 1994, he cited the death of his brother-in-law’s sister from complications of an illegal abortion as a touchstone.

“Since that time, my mother and my family have been committed to the belief that we can believe as we want, but we will not force our beliefs on others on that matter,” Romney said during a debate.

Romney even appeared that year at a fund-raiser for Planned Parenthood—an organization he has pledged to de-fund if elected president.

In 2002, as a candidate for Massachusetts governor, Romney said he would “respect and fully protect a woman’s right to choose.”

But Romney wrote in a 2005 op-ed in the Globe that his “convictions have evolved and deepened during [his] time as governor.” He began to take pro-life stances, explaining that it had become difficult to reconcile his personal belief about abortion with the political position he had taken for years.

At a Republican presidential debate in 2007, Romney said he “would welcome a circumstance where there was such a consensus in this country that we said we don’t want to have abortion in this country at all, period.” He added that he would be “delighted to sign” a bill banning all abortions but added “that’s not where America is today.”

The Obama campaign cites those debate remarks as evidence to support its claim that Romney opposes abortions for victims of rape and incest.

But more recently, Romney wrote in a 2011 op-ed in the National Review that he is “pro-life and believe[s] that abortion should be limited to only instances of rape, incest, or to save the life of the mother.”

Ryan’s longtime position has been to permit abortion only when a woman’s life is endangered by a pregnancy.